This project expands the regional center concept to demonstrate and make available the usefulness of centralization in the aid of community physicians who care for patients suspected or found to have trophoblastic disease (benign or malignant). To achieve these goals we propose: Continued extension of educational efforts through local, regional, and national meetings, conferences, seminars, and publications; an expanded HCG assay facility utilizing immunoassay and radioimmunoassay techniques for use in demonstration of methodology as well as usefulness of highly accurate and sensitive techniques for monitoring disease states; consultative assistance to the community physician for review of histopathology, aid in diagnosis, and support for chemotherapeutic techniques; and to provide an in-patient treatment facility (there is no additional cost to this project) for selected patients. Thus, the center concept will be expanded and utilized to make available current techniques for all patients who have problems with gestational trophoblastic disease.